mirror of
https://github.com/sqlite/sqlite.git
synced 2025-11-11 01:42:22 +03:00
Further foundation prep work prior to starting to flesh-out the
optimizeAggregateUseOfIndexedExpr() routine. FossilOrigin-Name: 23145fe999ff74d787a3999baedd4ffe755c5f1f1275082ed0338ba637ecc56e
This commit is contained in:
drh
171
src/select.c
171
src/select.c
@@ -6204,9 +6204,106 @@ void sqlite3SelectPrep(
|
||||
sqlite3SelectAddTypeInfo(pParse, p);
|
||||
}
|
||||
|
||||
#if TREETRACE_ENABLED
|
||||
/*
|
||||
** Assign register numbers to all pAggInfo->aCol[] and pAggInfo->aFunc[]
|
||||
** entries.
|
||||
** Display all information about an AggInfo object
|
||||
*/
|
||||
static void printAggInfo(AggInfo *pAggInfo){
|
||||
int ii;
|
||||
for(ii=0; ii<pAggInfo->nColumn; ii++){
|
||||
struct AggInfo_col *pCol = &pAggInfo->aCol[ii];
|
||||
sqlite3DebugPrintf(
|
||||
"agg-column[%d] pTab=%s iTable=%d iColumn=%d iMem=%d"
|
||||
" iSorterColumn=%d %s\n",
|
||||
ii, pCol->pTab ? pCol->pTab->zName : "NULL",
|
||||
pCol->iTable, pCol->iColumn, AggInfoColumnReg(pAggInfo,ii),
|
||||
pCol->iSorterColumn,
|
||||
ii>=pAggInfo->nAccumulator ? "" : " Accumulator");
|
||||
sqlite3TreeViewExpr(0, pAggInfo->aCol[ii].pCExpr, 0);
|
||||
}
|
||||
for(ii=0; ii<pAggInfo->nFunc; ii++){
|
||||
sqlite3DebugPrintf("agg-func[%d]: iMem=\n",
|
||||
ii, AggInfoFuncReg(pAggInfo,ii));
|
||||
sqlite3TreeViewExpr(0, pAggInfo->aFunc[ii].pFExpr, 0);
|
||||
}
|
||||
}
|
||||
#endif /* TREETRACE_ENABLED */
|
||||
|
||||
/*
|
||||
** Analyze the arguments to aggregate functions. Create new pAggInfo->aCol[]
|
||||
** entries for columns that are arguments to aggregate functions but which
|
||||
** are not otherwise used.
|
||||
**
|
||||
** The aCol[] entries in AggInfo prior to nAccumulator are columns that
|
||||
** are referenced outside of aggregate functions. These might be columns
|
||||
** that are part of the GROUP by clause, for example. Other database engines
|
||||
** would throw an error if there is a column reference that is not in the
|
||||
** GROUP BY clause and that is not part of an aggregate function argument.
|
||||
** But SQLite allows this.
|
||||
**
|
||||
** The aCol[] entries beginning with the aCol[nAccumulator] and following
|
||||
** are column references that are used exclusively as arguments to
|
||||
** aggregate functions. This routine is responsible for computing
|
||||
** (or recomputing) those aCol[] entries.
|
||||
*/
|
||||
static void analyzeAggFuncArgs(
|
||||
Parse *pParse,
|
||||
AggInfo *pAggInfo,
|
||||
NameContext *pNC
|
||||
){
|
||||
int i;
|
||||
assert( pAggInfo!=0 );
|
||||
pNC->ncFlags |= NC_InAggFunc;
|
||||
for(i=0; i<pAggInfo->nFunc; i++){
|
||||
Expr *pExpr = pAggInfo->aFunc[i].pFExpr;
|
||||
assert( ExprUseXList(pExpr) );
|
||||
sqlite3ExprAnalyzeAggList(pNC, pExpr->x.pList);
|
||||
#ifndef SQLITE_OMIT_WINDOWFUNC
|
||||
assert( !IsWindowFunc(pExpr) );
|
||||
if( ExprHasProperty(pExpr, EP_WinFunc) ){
|
||||
sqlite3ExprAnalyzeAggregates(pNC, pExpr->y.pWin->pFilter);
|
||||
}
|
||||
#endif
|
||||
}
|
||||
pNC->ncFlags &= ~NC_InAggFunc;
|
||||
}
|
||||
|
||||
/*
|
||||
** An index on expressions is being used in the inner loop of an
|
||||
** aggregate query with a GROUP BY clause. This routine attempts
|
||||
** to adjust the AggInfo object to take advantage of index and to
|
||||
** perhaps use the index as a covering index.
|
||||
**
|
||||
*/
|
||||
static void optimizeAggregateUseOfIndexedExpr(
|
||||
Parse *pParse, /* Parsing context */
|
||||
Select *pSelect, /* The SELECT statement being processed */
|
||||
AggInfo *pAggInfo, /* The aggregate info */
|
||||
NameContext *pNC /* Name context used to resolve agg-func args */
|
||||
){
|
||||
#if TREETRACE_ENABLED
|
||||
if( sqlite3TreeTrace & 0x80000 ){
|
||||
IndexedExpr *pIEpr;
|
||||
TREETRACE(0x80000, pParse, pSelect,
|
||||
("Attempting to optimize AggInfo for Indexed Exprs\n"));
|
||||
for(pIEpr=pParse->pIdxEpr; pIEpr; pIEpr=pIEpr->pIENext){
|
||||
printf("data-cursor=%d index={%d,%d}\n",
|
||||
pIEpr->iDataCur, pIEpr->iIdxCur, pIEpr->iIdxCol);
|
||||
sqlite3TreeViewExpr(0, pIEpr->pExpr, 0);
|
||||
}
|
||||
printAggInfo(pAggInfo);
|
||||
}
|
||||
#else
|
||||
(void)pSelect; /* Suppress unused-parameter warnings */
|
||||
#endif
|
||||
pAggInfo->nColumn = pAggInfo->nAccumulator;
|
||||
analyzeAggFuncArgs(pParse, pAggInfo, pNC);
|
||||
}
|
||||
|
||||
/*
|
||||
** Allocate a block of registers so that there is one register for each
|
||||
** pAggInfo->aCol[] and pAggInfo->aFunc[] entry in pAggInfo. The first
|
||||
** register in this block is stored in pAggInfo->iFirstReg.
|
||||
*/
|
||||
static void assignAggregateRegisters(Parse *pParse, AggInfo *pAggInfo){
|
||||
assert( pAggInfo!=0 );
|
||||
@@ -6630,60 +6727,6 @@ static int sameSrcAlias(SrcItem *p0, SrcList *pSrc){
|
||||
return 0;
|
||||
}
|
||||
|
||||
#if TREETRACE_ENABLED
|
||||
/*
|
||||
** Display all information about an AggInfo object
|
||||
*/
|
||||
static void printAggInfo(AggInfo *pAggInfo){
|
||||
int ii;
|
||||
for(ii=0; ii<pAggInfo->nColumn; ii++){
|
||||
struct AggInfo_col *pCol = &pAggInfo->aCol[ii];
|
||||
sqlite3DebugPrintf(
|
||||
"agg-column[%d] pTab=%s iTable=%d iColumn=%d iMem=%d"
|
||||
" iSorterColumn=%d %s\n",
|
||||
ii, pCol->pTab ? pCol->pTab->zName : "NULL",
|
||||
pCol->iTable, pCol->iColumn, AggInfoColumnReg(pAggInfo,ii),
|
||||
pCol->iSorterColumn,
|
||||
ii>=pAggInfo->nAccumulator ? "" : " Accumulator");
|
||||
sqlite3TreeViewExpr(0, pAggInfo->aCol[ii].pCExpr, 0);
|
||||
}
|
||||
for(ii=0; ii<pAggInfo->nFunc; ii++){
|
||||
sqlite3DebugPrintf("agg-func[%d]: iMem=\n",
|
||||
ii, AggInfoFuncReg(pAggInfo,ii));
|
||||
sqlite3TreeViewExpr(0, pAggInfo->aFunc[ii].pFExpr, 0);
|
||||
}
|
||||
}
|
||||
#endif /* TREETRACE_ENABLED */
|
||||
|
||||
/*
|
||||
** An index on expressions is being used in the inner loop of an
|
||||
** aggregate query with a GROUP BY clause. This routine attempts
|
||||
** to adjust the AggInfo object to take advantage of index and to
|
||||
** perhaps use the index as a covering index.
|
||||
**
|
||||
*/
|
||||
static int optimizeAggregateUsingIndexedExpr(
|
||||
Parse *pParse, /* Parsing context */
|
||||
Select *pSelect, /* The SELECT being coded */
|
||||
AggInfo *pAggInfo /* The aggregate info */
|
||||
){
|
||||
#if TREETRACE_ENABLED
|
||||
if( sqlite3TreeTrace & 0x80000 ){
|
||||
IndexedExpr *pIEpr;
|
||||
TREETRACE(0x80000, pParse, pSelect,
|
||||
("Attempting to optimize AggInfo for Indexed Exprs\n"));
|
||||
for(pIEpr=pParse->pIdxEpr; pIEpr; pIEpr=pIEpr->pIENext){
|
||||
printf("data-cursor=%d index={%d,%d}\n",
|
||||
pIEpr->iDataCur, pIEpr->iIdxCur, pIEpr->iIdxCol);
|
||||
sqlite3TreeViewExpr(0, pIEpr->pExpr, 0);
|
||||
}
|
||||
printAggInfo(pAggInfo);
|
||||
}
|
||||
#endif
|
||||
return 0;
|
||||
}
|
||||
|
||||
|
||||
/*
|
||||
** Generate code for the SELECT statement given in the p argument.
|
||||
**
|
||||
@@ -7465,19 +7508,7 @@ int sqlite3Select(
|
||||
}else{
|
||||
minMaxFlag = WHERE_ORDERBY_NORMAL;
|
||||
}
|
||||
for(i=0; i<pAggInfo->nFunc; i++){
|
||||
Expr *pExpr = pAggInfo->aFunc[i].pFExpr;
|
||||
assert( ExprUseXList(pExpr) );
|
||||
sNC.ncFlags |= NC_InAggFunc;
|
||||
sqlite3ExprAnalyzeAggList(&sNC, pExpr->x.pList);
|
||||
#ifndef SQLITE_OMIT_WINDOWFUNC
|
||||
assert( !IsWindowFunc(pExpr) );
|
||||
if( ExprHasProperty(pExpr, EP_WinFunc) ){
|
||||
sqlite3ExprAnalyzeAggregates(&sNC, pExpr->y.pWin->pFilter);
|
||||
}
|
||||
#endif
|
||||
sNC.ncFlags &= ~NC_InAggFunc;
|
||||
}
|
||||
analyzeAggFuncArgs(pParse, pAggInfo, &sNC);
|
||||
if( db->mallocFailed ) goto select_end;
|
||||
#if TREETRACE_ENABLED
|
||||
if( sqlite3TreeTrace & 0x20 ){
|
||||
@@ -7566,7 +7597,7 @@ int sqlite3Select(
|
||||
goto select_end;
|
||||
}
|
||||
if( pParse->pIdxEpr ){
|
||||
optimizeAggregateUsingIndexedExpr(pParse, p, pAggInfo);
|
||||
optimizeAggregateUseOfIndexedExpr(pParse, p, pAggInfo, &sNC);
|
||||
}
|
||||
assignAggregateRegisters(pParse, pAggInfo);
|
||||
eDist = sqlite3WhereIsDistinct(pWInfo);
|
||||
|
||||
Reference in New Issue
Block a user